Lamp basing machinery



Feb. 2, 1960 D. J. DWINELL' ET AL 2 LAMP BASING MACHINERY Filed Feb. 10,1958 5 Sheets-Sheet 2 INVENTORS DWWWTADWWWML -aawumlueluorr BY IHTHARW aA4xamer FRwMKiM0nuHr Feb. 2, 1960 D. J. DWINELL ET AL LAMP BASINGMACHINERY 5 Sheets-Sheet 4 Filed Feb. 10, 1958 INVENTORS DWIGHT J.DWI/(ELL GL'OKGE A. [LL/0T7 Feb. 2, 1960 A D. J. DWINE LL ETAL LAMPBASING MACHINERY Filed Feb. 10, 195B 5 Sheets-Sheet 5 United States LAMPBASING MACHINERY Application February 10, 1958, Serial No. 714,327

8 Claims. (Cl. 29-25.19)

This invention relates in general to the manufacture of lamps. Moreparticularly, the invention relates to the operations of preparing lampleads for basing, the threading of the leads through bases, and theactual basing of the lamps.

High speed lamp manufacture requires that processing operations bemechanized wherever possible. In the particular case of elongatedtubular lamps of which fluorescent lamps are typical, a major stepforward has been made by the relatively recent development of horizontalmachinery on which the processing operations are carried out while thelamps are in a horizontal position.

The horizontal machinery consists usually of a conveyor which moves thelamps along a predetermined path. Disposed at both sides of the conveyorare similar devices for performing certain manufacturing operations onthe lamps during their travel along the aforesaid path. After suchoperations as lamp sealing, evacuation, gas fill and tipping off areperformed by suitable automatic devices, bases must be placed on thelamps. Electrical contacting pins on the bases must be connected insuitable conducting relationship to lead wires of the lamps, and thebases themselves must be firmly attached mechanically to the glass endsof the lamps. The usual practice is to solder or weld the lamp leads tothe base contacts or pins and to cement the bases to the glass of thelamp by a tenaciously adherent cement, such as a Bakelite cement whichmay be heat cured to assure the permanent adherence of the bases to thelamps.

There are some lamps, for example, the so-called instant-start typeswhich have single contact bases. That is, each base is provided withonly one conducting mem her for contacting a single contact receptacleat each end of the socket in which the lamp is used. The conductingmember of the base is usually a centrally located, roundended, metallicthimble which projects outwardly from an annular member made of Bakeliteor other insulating material. The annular member is dished toaccommodate a ring of basing cement and to fit over the end of the lampto which it is cemented. The metallic thimble has an opening formed inits extreme end to receive leads from the lamp.

Because the lamps are provided with oxide coated filamentary electrodesthrough which current must be passed during manufacture, two leads arenecessarily present at each end of the lamp. It is desirable for severalreasons that both these leads be electrically connected to the singlecontact of the base. These leads are usually of the order of .020"diameter each and the opening in the base contact runs about .059 to.060 diameter. Obviously, there is sufficient clearance to pass theleads through the opening, but the fit is relatively close. The fit mustbe maintained relatively close or the subsequent soldering operationwill not join the leads and the base member in good electrical contact.

First attempts at threading the two leads through a base contact werepurely manual. The operator merely drew the leads out straight andparallel to each other Patented Feb. 2, 1960 lamp end. A slight twistingmotion applied to the base aided the manual threading operation.Subsequently, a conically tapered base contact was used in an earlyautomatic threader. The conical internal surface facilitated threading,but the conical external surface failed to make good contact in thereceptacle of the socket designed to hold it. A mechanical threadingdevice which merely drew the leads out straight and held them in thatposidon while a base was forced over them was also tried. This devicewas unsatisfactory in numerous respects, but primarily because jammingof the leads rather than the desiredthreading too often occurred.

It is, therefore, an object of the present invention to provideautomatic, trouble-free threading of lamp leads and basing of lamps.

it is a further object to avoid the jamming of leads encountered inusing previously known equipment.

A still further object is to further mechanize the manufacture ofdischarge devices such as fluorescent lamps.

Another object is to reduce the cost of lamps by mechanization ofprocess steps and elimination of waste and duplication of effort inlead-threading and basing of lamps.

In general, the present invention is organized about a conveyor alongwhich lamps are indexed. At each dwell position of the lamps, one ormore of various processing operations take place. For purposes ofdescription of the present invention it may be assumed that such processsteps as evacuation, gas-filling and tipping have been completed as havecertain electrical operations and checks on the lamp. Two leads extendfrom each end of the lamp and may be oriented in any random position,when the lamps reach the point on the conveyor at which the presentinvention comes into play.

At a dwell position of the lamp, a rotating head advances toward eachend of the lamp. Each of the rotating heads includes a pair of jawswhich are sprung wide apart as the head advances toward the lamp end.The head stops its advance adjacent the lamp, but rotation continues.When, however, retraction of the head occurs, the jaws close tightly. Asthe rotary retractive movement begins, the wires are seized by the jawsand are then given a long helical twist as retraction continues. Thejaws remain closed even after they are re tracted to a point beyond thefull length of the leads and do not reopen until a new cycle ofoperation begins.

The lamp is then indexed forward to a new dwell position, adjacentbase-threading heads. Guide structures which may be in the form ofgravity feed slides are dis, posed at'each end of the lamp and carrybases which have previously been filled with basing cement. The casesare released one by one to vacuum chucks adjacent the ends of the lamp.Each of the vacuum chucks consists of a hollow rammer shaft whichrotates and which may be advanced and retracted relative to the lampend. The base carried by the hollow shaft is rotated and advanced towardthe lead wires of the lamp which were provided with a helical twist atthe previous dwell position. The base has a central contact pin in whichan opening is formed. The base is rotated during its travel toward thelamp end, the rotation aiding the lead wires to enter and pass throughthe relatively small hole at the end of the base pin. As the baseapproaches the glass end of the lamp, rotation of the hollow shaft isdiscontinned by the disengagement of a clutch. Finally, as

received by the vacuum chuck at the end of the hollow shaft to repeatthe threading cycle.

For a better understanding of the present invention together with otherand further objects, features and advantages, reference should be madeto the following description of a preferred embodiment thereof whichshould be read in connection with the accompanying drawings in which:

Fig. 1 is a plan view of an embodiment of the present invention;

Fig. 2 is a side elevation partly in section of the wire twistingportion of the present invention;

Fig. 3 is a side elevation partly in section of the basethreadingportion of the present invention;

Fig. 4 is an enlarged side elevation, partly in section, of workingelements of the mechanism shown in Fig. 3;

Fig. 4a is a detailed sectional view of the vacuum breaking device ofthe base-threader;

Fig. 5 is a detailed view of the jaws of the wire twisting mechanism,the jaws being shown in an open position; and

Fig. 6 is a further detailed view of the jaws of the wire twistingmechanism of the present invention, the jaws being shown in a closedposition.

General layout and operation Understanding of the present invention maybe facilitated by a general consideration of Fig. 1 before going moredeeply into structural details. In the various figures of the drawings,a convention has been adopted with regard to reference numerals.Numerals of the 100 series refer to the wire twisting portion andreference numerals of the 200 series refer to the base-threading portionof the invention, while numerals less than 100 are applied to elementscommon to both portions.

A number of fluorescent lamps are shown at the right hand side of Fig. 1of the drawing. These lamps are indexed along a conveyor 12'by a chain13 on which the lamps are retained. Lamps reaching the point indicatedby the lowermost lamp 14 have been evacuated, gas-filled and tipped.Various electrical operations and checks such as the initial breakdownalso are performed prior to the operations which are carried out by thepresent invention. To all intents and purposes, the lamp 14 issubstantially complete but no base has yet been applied.

Electrical connecting members such as the lead wires 15 extend from thelamps and may have been given a preliminary orientation at a previouspoint to draw them more or less axially outward from the lamps. Thispreliminary orientation is not essential to proper operation of thepresent invention, although operation is aided to some extent if theleads are so treated. Apparatus is provided adjacent the conveyor onboth sides in order that processing operations may be performedsimultaneously at both ends of the lamps as they proceed along theconveyor. In other words, apparatus which is a mirror image of thatshown in Fig. 1 is disposed at the opposite ends of the lamps on theother side of the conveyor which is not shown.

The general operation of the present invention is such that as a lamp isindexed into the position occupied by the lamp 16, second from thebottom in the showing of Fig. 1, a pair of jaws are advanced toward theend of the lamp. The jaws are caused to swing open as they are advancedtoward the lamp and they are rotated continuously during their entireforward progress. The rotaltion is imparted to the jaws by means of amotor, a reduction gear, and a pair of pulleys joined by a V-belt. Thesecond pulley is pinned to a sleeve on which the jaws are mounted and,in this manner, the jaws are maintained in continuous rotation.

As will be explained in greater detail below with reference tosubsequent figures of the drawing, the jaws are advanced by means of acam driven lever the end of which is slotted to accommodate a trunnionblock.

When the rotating jaws in their open position reach a point adjacent theend of the lamp, their forward motion is discontinued.

Retraction of the entire mechanism then occurs in response to continuedaction of the cam driven lever on the trunnion block. As the retractionbegins, the jaws close, seizing upon the lead wires extending from theend of the lamp. The retraction combined with the rotating of the jawscauses the leads to be twisted hclically. Furthermore, the retractingaction of the closed jaws draws the helically twisted leads out roughlyalong the axis of the lamp.

At the next index of the conveyor chain 14, the lamp is carried to theposition indicated by the lamp 17 shown third from the bottom in Fig. 1of the drawing. Here it is desired to thread a base on the helicallytwisted lead wires which are now prepared to receive it. The base isprovided with a contact pin which has a small central opening, and it isdesired to pass the twisted leads through that opening.

Now, a rammer shaft having an advancing and retracting motion is used.During the retracting motion, a base is dropped by an escapement deviceagainst a stop adjacent the end of the lamp. A vacuum chuck on the endof the base rammer shaft picks the base from the stop and carries ittoward the end of the lamp. As the base is moved toward the end of thelamp, it is rotated causing the helically twisted'leads to go easilythrough the opening in the pin of the base. In this instance, however,in contrast to the action of the lead-twisting device, the rotation ofthe tool is not continuous. A clutch in the rammer shaft drivedisengages as the base approaches the end of the lamp. This is necessarybecause a small quantity of basing cement is carried around the inneredge of the base and it would be removed or displaced if rotation wereto continue when the basing cement comes into contact with the end ofthe lamp.

Not only is the rotating motion discontinued when the base nears itsintended final position on the lamp, but also the vacuum exerted on thebase through the hollow shaft is broken by the opening of a port in theshaft adjacent the clutch and the base is merely pressed onto the lampend. Thus, as the retracting motion of the base-threading mechanismfollows, there is no tendency for the base to be withdrawn from the lampend.

With the aid of the foregoing general explanation of layout andoperation, understanding of structural details and specific processingsteps of the embodiment of the invention described below should befacilitated.

The wire twisting mechanism The upper most portion of the wire twistingmechanism, amongst other apparatus, is shown in the plan view of Fig. 1.However, the side elevation of Fig. 2 provides a better reference to beused in connection with the description immediately following.

Basic structural support for the entire apparatus is derived from aframe 99 on which a support bracket 100 is bolted. A fulcrum shaft 101is supported in a downwardly depending extension of a support memberwhich, in turn, is bolted to the bracket 100. A major actuating lever102 is pivoted on the fulcrum shaft and carries at its end a rotatablecam follower 103 bearing upon a contoured cam 104. A rod 105, springloaded in a manner explained below, is pivotally attached to the lever102 adjacent its other or upper end and maintains the follower 103 incontact with the earn 104.

A finger cam 107 is provided on the same shaft as cam 104. A finger camfollower 108 is rotatably attached to a lever 109 and bears upon thefinger cam 107. At the other end of the lever 109 there is pivotallyattached a finger spring guide 110. The finger spring guide extendsthrough matching openings in the support bracket 100 and in a fingerbracket 113 which is bolted to the support bracket 100. At the upper endof the finger bracket 113 is a finger stud 114 about which a finger 115pivots. A finger stop 117 adjustable in its bearing upon the bracket 113is provided in a depending portion of the finger.

At the upper end of the finger spring guide 119 a pivotal attachment,not shown, is made to the finger 115. A compression spring 120 disposedbetween the finger spring cup 119 and the adjustable finger springcollar 121 maintains the finger 115 in the normally raised position inwhich it is shown, and also tends to hold the follower 108 against thefinger cam 107. in its normally raised position, as it is shown, thefinger 115 is adjacent the end of the fluorescent lamp 116. The fingerthus prevents the lamp 116 from moving to the right off the conveyorbed;

The mechanism for performing the wire twisting funetion also derivesbasic support from the bracket 100. Bolted to the bracket 100 is acasting 130 at the upper end of which two aligned cylindrical membersare formed. The member 131 is at the left and the member 132 at theright as seen in Pg. 2. A third circular opening is formed in thecasting at 133 to accommodate the spring rod 105. In a depending portionof the casting 130 a fourth opening is formed for the fulcrum shaft 101.

Bushings are inserted in the cylindrical members 131 and 132. A tubularslide 133 passes through the bushing of the member 131 and a sleeve 134is carried in the bushing of the member 132. Lubrication is provided forthe contacting surfaces'of the slide 133 and the bushing of member 131by a reservoir assembly 135. An oiling device 136 permits lubrication ofthe contacting surfaces of the sleeve 134 and the bushing of member 132.

A rod 137 is spring-loaded against the sleeve 134- by means ofacompression spring 138. A screw 139 is threaded into a housing 140 tobear against the spring 135 to adjust the pressure that the rod 137exerts upon the sleeve 134. The'sleev'e 134- has a flanged end againstwhicha ball bearing assembly 141 is retained by means of a pair of checknuts 142 threaded on the sleeve 134. A housing143 encloses the ballbearing assembly 141 and the housing is'att'ached by means of screws toa pulley 144. A V-b'elt 145 driven by a motor, reduction gears andpulley (see Fig. 1), engages the pulley 144- The pulley 144 is fixed tothe tubular slide 133 by a pinor'by a screw threaded into the pulley andbearing on a'fiat in the slide 133. In this manner, rotation is impartedto the tubular slide 133 and to its attached jaw support member 123 onwhich the jaws are mounted. Dietailsof the support and structure of thejaws are given below in conneetion'with an enlarged view of the jaws andtheir associated structure. 7

At the' other end of the mechanism, adjustable check nuts 149 areprovided at the end of the sleeve 134. A rod end-150 is threaded on theend of the shaft 125 and held in'place by a lock nut. Pivotally attachedto the rod end is a trunnion block 151 arranged for sliding actionin aslot 152 formed in the end of the lever 102. An adjustable forwardmotion limit step 153 designed to contact a surface of the member 132extends inwardly from a point adjacent the end of the lever 102. Thepreviously mentioned spring rod 105 is pivotally attached to the lever102 just below the stop 153. The spring rod passes through the openingat 133 in the support 130 and is urged to the left, as seen in Fig. 2,by the action of a compression spring 155 which is held betweena springcup 156 and the wall surrounding the opening at 133.

At thispoint, an explanation of the operation of this p'o'rtionoftheapparatus with the exception of the details of jaw operation, may beuseful to promote understanding of the invention. The cam 104 is rotatedcontinuou 1y by a primary power source, not shown. After a lamp isindexed into position adjacent the wire twister, the finger cam 107permits the follower 103 to move inwardly to the left as shown in thedrawing under the influence of the compression spring 120 which alsoforces the finer 115 up to the position in which it is shown in Fig. 2.Neglecting for the moment the operation of the wire twisting mechanism,if rotation of the cam 104 continues until the follower 108 is picked upby the plateu of the cam 107, the rod is drawn downwardly to swing thefinger downwardly and away from the lamp end against which it abuts. Theentire purpose of the finger 116 is to prevent lamps from being drawnendwise off the conveyor during the wire twisting operation.

Clearly, however, the timing of the operation of the finger 115 iscritical to prevent interference between the finger, the lamps as theyare indexed, and the twisting mechanism. Motions of the conveyor chain,the wire twister and the finger are therefore carefully synchronized byproper cam design and relative rotation.

Reverting to primary functions, the wire twisting operation itself mustnow be considered. Action is initiated by the eccentricity of the cam104. As the cam 104 rotates from the position in which it is shown, thecam follower 103 is moved in a generally upward direction. The lever 102pivots about the fulcrum 101 against the pressure of the compressionspring 155. The same spring 155 mantains the follower 103 against thecontoured surface of the cam 104 at all times.

Taking the downward movement of the follower 103 into considerationfirst, the lever 102 pivots about the fulcrum 101 in a counter-clockwisedirection. The upward movement of the right hand end of the lever 102causes the trunnion block 151 to move to the left as shown in thedrawing.

Movement of the trunnion block 151 to the left causes a correspondingmovement of the shaft 125. As is explained below in connection with thedetailed showing and description of the jaws, thse members are forcedopen against spring pressure. The shaft moves within the sleeve 134 foradistance great enough to open the jaws before the sleeve 134 moves atall. The friction engendered by the rod 137 bearing on the sleeve 134prevents that sleeve from moving until the shaft 125 has moved as far asthe check nuts 149 permit. Movement of the shaft 125 ceases when thecheck nuts 149 encounter the end of the cylindrical member 132. At thistime, the entire rotary mechanism moves to the left, the slide 133moving in the bushing in the member 131 and the sleeve 134 moving in thebushing in the member 132. The slide 133 is rotated continuously duringthis movement, as, of course, are the jaws 124 which are held by the jawsupport 123 on the slide 133. This leftward movement of the entirerotary mechanism continues until the adjustable stop 153' encounters theend surface of member 132.

At about this time the contoured cam surface begins to carry the camfollower 103 in an upward direction. The lever 102 pivots about thefulcrum shaft 101 and the trunnion block 151 is moved to the right. Thefirst action occurring on the withdrawal of the trunnion block 151 is amovement to the right of the shaft 125, the pressure of the rod 137 onthe sleeve 134 inhibiting its movement. Movement of the shaft 125 to theright causes the jaws to close as will be shown and explained in greaterdetail hcreinbelow. As the jaws close, they seize upon the lead wires118. Retraction of the slide 133 and the sleeve 134 commences as thetrunnion blocks 151 are drawn further to the right by the action of thelever 102.

With the jaws rotating continuously and seized upon the lead wires 113,the retracting movement to the right causes the lead wires to be drawnout and twisted into a helix. Retraction of the entire unit continuesuntil the cam follower 103 reaches the point of greatest radius on thecam 104, at which point the jaws are beyond the furthest extension ofthe lead wires.

Base threading mechanism After the lead wires have been twisted into ahelix in the manner described above, the fluorescent lamp is indexed toa new position indicated by lamp 17 which is shown in the position thirdfrom the bottom in Fig. 1. Also, as is shown in Fig. 1, and in someparticulars more clearly shown in Fig. 3, a device is provided at thispoint for completing the basing function by threading bases onto thelead wires which were prepared by the twisting operation performed atthe previous position. In Fig. 3 some of the basic structural elementsare shown fragmentarily as, for example, the basic support bracket 201which is attached to the conveyor frame. This bracket can be the same asbracket 100 previously described or may be a separate member. An outwardextension of the bracket 201 has bolted to it a support which includes adownwardly depending fulcrum shaft bearing member 203. A fulcrum shaft204 is held in the member 203 and provides a pivot for the cam lever206. The lower portion of the cam lever 206 carries a cam follower 208which bears upon a contoured cam 209. The cam 209 may have a slightlyroughened surface for purposes explained below. A spring lever 210 isbolted to the lower portion of the cam lever 206 and a tension spring212 is attached to the end of the spring lever 210 to retain the camfollower 208 in contact with the contoured surface of the cam 209. Theupper end of cam lever arm 206 is provided with a catch 214, a stopsurface 216 and a yoke 218. A latch 220 designed to cooperate with thecatch 214 is normally held from engagement with the catch by a tensionspring 222 which is stretched between the end of the latch and a pin inan arm 224 of the support member. A solenoid 226 is retained on theextending portion of the bracket 201 by means of a plate 228 which isbolted to the bracket. The solenoid has a shaft 230 extending outwardlyfrom its core and attached pivotally to the latch 220. A motor support232 which may be independent or derive its basic support from theconveyor frame, carries a motor 234 which drives a pulley 235 through areduction gear 236. A V-belt 238 connects the drive pulley 235 to asecond driven pulley 240.

A vacuum line 241 is connected at the left end of a base rammer shaft242. The base rammer shaft 242 is hollow throughout its entire lengthpermitting the vacuum to be exerted at the end adjacent the lamp 245. Avacuum line support 246 extends outwardly from the basic support arm 224and retains the vacuum line 241 in its proper position. Means areprovided to break the vacuum in the base rammer shaft at a pointintermediate its length as is illustrated in another figure of thedrawing and described in detail below.

A feeder sleeve 248 surrounds the base rammer shaft and has a threadedend on which a check nut 249 is adjustably engaged. The upper end of thearm 224 terminates in a cylindrical member 250 which serves as the basefeed bracket. To the right of the base feed bracket as seen in thedrawing is a heavy compression spring 251. A thrust bearing 252 isprovided between the compression spring and the previously mentionedpulley 240. These three elements are mounted upon the feeder sleeve 248which has a flanged end against which the pulley abuts. To the right ofthe pulley 240 is a clutch mechanism which includes a clutch shoe 254and a flanged clutch collar 256. The base rammer shaft 242 as shown inthe drawing is provided with a flat against which a screw through theclutch collar bears to maintain the collar fixed against rotationrelative to the base rammer shaft.

At the upper left of Fig. 3 (and more clearly and in enlarged detail inthe same area of Fig. 4), is a base supply guide 257. Along this guide,a supply of bases 258 are led to where they are presented to a chuck 261at the end of the base rammer shaft 242. The bases are circular in shapeand a pair of spaced stop fingers of which finger 260 is typical areprovided to serve as an escapement mechanism. The two fingers go betweenthe two lowermost bases at either side of their point of contact.

In the yoke 218 of the cam lever arm, a trunnion pin 262 is disposed forsliding movement. The trunnion pin is pivotally attached to the baserammer shaft 242 by means of a clamping device and is also connected toan overtravel mechanism. The overtravel mechanism includes a tensionspring 264 which is stretched between the base feed guide 257 and aspring plate 265. A cap screw 266 is provided to adjust the position ofthe spring plate 265 and thereby to adjust the tension of the spring264. The overtravel function is explained in greater detail hereinbelow,its function being accomplished primarily by the positioning of ashoulder screw 270 in the slot 271 of the mechanism.

The extent of forward movement of the lever arm 206 is controlled by anadjustable cap screw 272 against which the stop surface 216 strikes atthe furthest forward point of movement of the upper portion of the leverarm 206.

An explanation of the phase of the basing operation for which theapparatus described immediately above is responsible may help inunderstanding the invention. When a lamp is indexed into the position atwhich lamp 245 is shown in Fig. 3 of the drawing, the base threadingoperation begins. The existing conditions include a vacuum being drawnthrough the vacuum connection 141 and extending through the entirelength of the base rammer shaft 242 to the base holding chuck 261. Also,the motor 234 is operating, causing the pulley 236 to drive the pulley240 rotating the base rammer shaft and its associated components. Thebase guide member 257 is filled with bases, one of which rests againstthe base stop 259. Furthermore, the solenoid 226 is de-energized,causing the latch 220 to be out of engagement with the catch 214 asshown in the drawing. A microswitch or similar device, not shown, isdisposed upon the conveyor and is so arranged that the energizingcircuit to the solenoid 226 remains open as long as fluorescent lampsare being indexed along the conveyor. In the absence of a lamp, theswitch is not tripped, causing the solenoid energizing circuit to remainclosed and the latch 220 to engage the catch 214 thereby preventing thelever arm 206 from moving about the fulcrum 204. The cam follower 208 isshown in a position adjacent the greatest radius of the cam 209. Afterthe roller 208 passes over the portion of greatest radius of the cam209, the tension spring 212 draws the spring lever 210 and the cam lever206 downward and to the left as shown in the drawing. The portion of theperiphery of the cam 209 which the follower 208 traverses at this timemay be slightly roughened to give a slight vibration to the cam lever206. As the device pivots about the fulcrum 204, the upper forked end ofthe lever arm 218 begins to move to the right. The base holding chuck261 encounters a base 258 resting on the base stop 259 and the base soencountered is held in the base chuck by reason of the vacuum existingthroughout the length of the base rammer shaft. Rotation of the baserammer shaft continues as the shaft moves to the right and a very lightvibration of the shaft also occurs because of the roughened surface ofthe cam 209. The vibration aids in passing the lead wires of the lampthrough the opening in the base 258.

The fingers 260 pass between the two lowermost bases on the guide 257until the fingers contact the front portion of the guide. The clutchshoe 254 remains in intimate contact with the pulley 240 by reason ofthe pressure exerted by the compression spring 251 on the thrust bearing252.

When the fingers 260 encounter the front portion of the base guide 257,the overtravel mechanism comes into play, as is most easily seen in Fig.4. Further movement of the trunnion 262 to the right is not effective tomove the finger 260 to the right. Instead, the finger support platemoves forward guided by the shoulder screw 27% which is disposed in theslot 271 in the support memher.

When the check nut 249 strikes the left hand surface of the feedermember 250, travel of the clutch sleeve 24% ceases. The clutch shoe 254breaks from the surface of the pulley 240 and rotation of the baserammer shaft ceases. This occurs just prior to seating of the base 258on the end of the lamp 245. Thus, as the base rammer shaft continues tothe right, the base is merely jammed on the end of the lamp and notrotated relative to the lamp end. Simultaneously with the breaking ofthe clutch, the vacuum within the base rammer shaft is broken by meansof a port 243 extending radially through the shaft adjacent the breakpoint of the clutch as shown in Fig. 4A. The clutch is shown in solidlines in its engaged position and in dashed lines in its disengagedpositon. The port 243 is similarly shown and it'will be noted that theport is open to atmospheric pressure when the clutch is disengaged.Thus, there is no tendency for the base to be retracted from the lampwhen the base rammer shaft is retracted as described below.

As the cam 209 continues its rotation and the radius increases, the camfollower 208 causes the upper portion of the lever arm 206 to move tothe left to retract the base rammer shaft. This action continues untilthe clutch is reengaged. The finger 260 is retracted and another basedrops into position against the base stop 259 awaiting the next thrustof the base rammer shaft when a new lamp has indexed into position.

Description and operation of jaws The structure and operation of thejaws which prepare the lead wires for basing by twisting them anddrawing them out along the axis of the lamp may best be understood byreferring to the enlarged showings of this device in Figs. 5 and 6. InFig. 5, the jaws are shown in the open position which they assume astheir advance toward the lamp takes place. As was previously explainedin connection with the view of the entire wire twisting mechanism, a jawsupport member 123 is attached at the end of the tubular slide 133. Thetubular slide is provided with a pair of flats on its outer surfacewhich are 90 degrees apart and which are engaged by lock screws passingthrough the jaw support at corresponding points.

As may be seen in Fig. 2, a pair of radial slots are cut indiametrically opposite areas of one face of the disk shaped jaw supportmember 123. In these slots, there are welded a pair of arms 161 and 162.These arms extend parallel to the axis of the support and terminate inrounded ends which are bored to accommodate fulcrum screws 163 and 164.Pivoted about each fulcrum screw is a jaw lever composed of an arm and aholder welded together at an obtuse angle. The levers are similar andthe bottom lever, as seen in Figs. 5 and 6, includes the arm 166 and theholder 167. The top lever includes the arm 168 and the holder 169.

Bolted to the arm 166 is a bushing 170 which may be eccentricallymounted for ease of operation. A similar bushing and bolting arrangementexists for the arm 168, but is hidden in the drawing. These bushings,one above the shaft 125 and the other'below it, are designed to becontacted by a pair of contact disks 171 and 172 which are locked to theshaft 125.

A tension spring 173 extends between pins or bolts on the holders 167and 169, respectively, and tends to hold them in the position shown inFig. 6. At the end of the holder 167, there is bolted an L-shapedgripper 175 and a similar gripper 176 is bolted to the holder 16 9. Bothgrippers have forked ends, and the gripper 176 has its forward endrelieved to permit the passage of the gripper 175 during the closingmovement.

The jaw operation is fairly obvious from the drawing. With the advanceof the shaft (to the left as' shown in the drawing) the disk 171contacts the upper and lower bushings on the arms 166 and 168 pushingthem forward and openings the jaws as the levers pivot about theirfulcrums 163 and 164. Similarly, when the shaft 125 retracts (to theright, as shown) the contact disk 172 contacts the bushings and thuspulls the jaws shut.

Although What has been shown is a preferred embodiment of the invention,numerous modifications within the scope of the invention willimmediately suggest themselves to those skilled in the art. Hence, theinvention should be limited only as required by the breadth of theappended claims.

What is claimed is:

1. Basing machinery for affixing a base having an opening formedtherethrough to a lamp having at least a pair of leads extendingoutwardly therefrom comprising jaws for seizing said leads, means forrotating and retracting said jaws from said lamp to form said leadssubstantially into a helix, a chuck for holding said base and means forrotating and advancing said chuck toward said lamp to thread saidhelically formed leads through said opening formed in said base.

2. Basing machinery for affixing a base having an opening formedtherethrough to a lamp having at least a pair of leads extendingoutwardly therefrom comprising jaws for seizing said leads, means forrotating and retracting said jaws from said lamp to form said leadssubstantially into a helix, a hollow chuck, means for applying a vacuumto said chuck to hold said base therein, means for rotating andadvancing said chuck toward said lamp to thread said helically formedleads through said opening formed in said base, and means fordiscontinuing said vacuum to said chuck to release said base therefromadjacent said lamp.

3. Basing machinery for affixing a base to the end of a lamp from whicha pair of leads extend, said base having an opening formed therethrough,comprising a lead preparing station, a base threading station, and meansfor indexing lamps sequentially to said stations, said lead preparingstation including a pair of jaws, means for continuously rotating saidjaws, means for advancing said jaws in open position toward said lampend, means for closing said jaws to seize upon said leads, means forrotating and retracting said jaws from said lamp end to form said leadssubstantially helically, said base threading station including a hollowchuck, an escapement mechanism for supplying bases one at a time to saidchuck, means for applying a vacuum to said hollow chuck to retain a basetherein, means for rotating and advancing said chuck toward said lampend to thread said helically formed leads through said opening in saidbase, and means for disconnecting said vacuum from said chuck to releasesaid base as said chuck approaches said lamp end.

4. Basing machinery for afiixing a base to the end of a lamp from whicha pair of leads extend, said base having an opening formed therethrough,comprising a conveyor for said lamps, a lead preparing station and abase threading station, said lead threading station being disposedadjacent said conveyor at a first point, means for indexing said lampsone after another along said conveyor to said first point, each saidlamp dwelling at said first point for a predetermined period of time, apair of jaws, a reciprocating support therefor, and means forcontinuously rotating said jaws included in .said lead preparingstation, means within said reciprocating support for opening said jaws,advancing said jaws toward a lamp dwelling at said first point, closingsaid jaws upon said leads, and retracting said jaws, the retraction androtation of said jaws causing said leads to be twisted helically anddrawn outwardly from said lamp, means for indexing said lamps one afteranother along said conveyor to a second point, said base threadingstation being adjacent said second point, each said lamp dwelling atsaid second point for said predetermined period of time, a hollow shaft,a vacuum line connected to one end of said shaft, and a chuck at theother end of said shaft for holding a base by means of said vacuum, asupply of bases adjacent said other end of said shaft, an escapementmechanism at said supply of bases for presenting bases one at a time tosaid chuck, means for rotating and advancing said shaft toward a lampdwelling at said second point on said conveyor, said chuck encounteringand holding a base during its advance, the advance and rotation of saidshaft and chuck threading a base upon said helically twisted leadsduring the dwelling of a lamp at said second point, a clutch in therotating means for said shaft, and means for disengaging said clutch toterminate rotation of said shaft as the base approaches the end of thelamp on which it is being threaded.

5. Apparatus as in claim 4 wherein a port is formed in said shaftadjacent said clutch, said port being opened to air pressure bydisengagement of said clutch to break the vacuum from said vacuum lineto said chuck.

6. Apparatus as in claim 4 wherein said means for rotating said hollowshaft includes a cam having a 7. Basing machinery for afiixing a base tothe end of a lamp from which a pair of leads extend, said base having anopening formed therethrough, comprising means for twisting said leadstogether into a substantially helical configuration, a hollow chuck,means for applying a vacuum to said chuck to retain a base therein,means for rotating and advancing said chuck to thread said helicallyformed wires through the opening in said base, means for substantiallysimultaneously breaking said vacuum in said hollow chuck anddiscontinuing the rotation of said chuck as said base approaches saidend of said lamp to release said base from said chuck and to preventrotation of said base relative to said end of said lamp as said baseapproaches contact therewith.

8. Apparatus as in claim 7 wherein said means for rotating and advancingsaid chuck includes means for imparting a light vibration to said baseto expedite the threading of said leads through said opening in saidbase.

